Document n9KBppyN3nzEKEjZ0X0w1LbL8

Blcc: Dr. D.V.N. Hardy/ MR. H.K. NASON. St.Louie (2) JXBiVSH oot Dr. H.R. Newman. , 8th September, 1955* ARQCLOR TOXICOLOQY Dear Howard, You will readily appreciate that we are very *uoh concerned with the toxicology of Aroolora, particularly as our development sales efforts In this field of Monsanto produots have# in the last six months or so, really begun to pay off. * Recently we reoeived through Dr. Kelly the findings of the Kettering Laboratory whioh as far as we were concerned included-entirely new data. In particular, the toxicity of Aroolor 1254 was demonstrated with a range of animals at a level of 1.5 mgrm./ou.m. At the same time there was no toxicity found for 1242 at concentration of 1.9 mgrm./cu.n. This in itself might be said to be surprising and perhaps lndloate some specific differences between the toxleitles of various grades of Aroolor. We would be most anxious to learn from you whether you aoeept the Kettering results as fully significant in a broad way, and whether this data is going to be made available to all. Fortunately, our Chief Medical Offloer, Dr. H.R. Newman, Is visiting 8t.Louis and will be discussing the significance of this Kettering work with Dr. Kelly. Here there is a convention that a faetor of 10 is used in translating animal toxloities to human toxleitles. In other words there would be an interpretation that Aroolor 1254 should not be used where atmospheres containing a quantity something less than . 0.15 mgAs./cu.m. results. Both gales and Development here are very anxious to handle this awkward problem in the right way and to remain in oomplete liaison with you on actions which might be neoessary. Perhaps it la particularly important to us as a very large proportion of our present sales do go to surface coating uses. HONS 095194 I WATER PCB-SD0000017733 2 V* had been giving consideration to setting some toxloologioal data aatabllshad for us on the Aroclors by Battalia in Germany Wh6 have good facilities for this type of work. However, we would certainly not do this without full discussion with you* To us there seams the neoeaslty of establishing quite a lot more data and we would be willing to arrange for some of this to be obtained if you think that this is a reasonable suggestion. Dr.NewBan's visit la particularly appropriate at this stage and of oourse it would be possible for ae~to disousa the hatter broadly during wy visit in late October* However, weanwhlle we would be host grateful to gain as huoh of the M.C.C. point of view as possible. J*W. BAKUm. HONS 095195 WATER_PCB-SD0000017734